Etude comparative de l’activité antioxydant de l’extrait brut de Thymus ciliatus ssp euciliatus et la ssp coloratus.

Abstract

In the context of nutrition and health, antioxidants play an essential role. And phenolic compound, which are present in many foods, are known for their beneficial properties. Antioxidants work by neutralizing free radicals, unstable molecules responsible for oxidative stress in the body. Phenolic compounds, such as flavonoids and phenolic acids, are abundantly found in fruits, vegetables, whole grains and herbs. They offer protection against cardiovascular diseases, cancer and other conditions related to aging. Antioxidant compounds are of great research interest due to their potential use as natural preservatives in foodstuffs, replacing synthetic antioxidants. In addition, these compound play a crucial role in the treatment of various diseases. In this study, we are interested in the analysis of phenolic compounds and the antioxidant activity of the crude extract of the aerial part of two aromatic and medicinal plants: Thymus ciliatus ssp coloratus and ssp euciliatus. These plants are part of the Lamiaceae family and are present spontaneously and widely in Algeria. They are still widely used in traditional medicine in many countries, especially as antiseptics and to treat respiratory problems. The extractions of the crude extracts of the aerial part of Thymus ciliatus from the two ssps were carried out by extraction methods using specific solvents for each extract. The evaluation of the antioxidant power by four different techniques, namely the reduction of iron FRAP, the trapping of the free radical DPPH, the trapping of hydrogen peroxide (H₂O₂) and the method of decolorization of beta-carotene in all extracts and fractions, shows that there is a certain conformity between the four techniques studied. Indeed, the crude extract of the aerial part of Thymus ciliatus ssp euciliatus exhibits a more pronounced antioxidant activity than ssp coloratus, by studies between the four methods which demonstrate the superiority of subspecies ssp euciliatus. Key words: Thymus ciliatus ssp color